The effect of semen/seminal fluid chemistry on women

"The finding that women who do not use condoms during sex are less depressed and less likely to attempt suicide than are women who have sex with condoms and women who are not sexually active, leads one researcher to conclude that semen contains powerfulâand potentially addictiveâmood-altering chemicals.

Study author Gordon G. Gallup, Ph.D., a psychologist at the State University of New York in Albany, also found that women who routinely had intercourse without condoms became increasingly depressed as more time elapsed since their last sexual encounter. There was no such correlation for women whose partners regularly used condoms."